Links in PDF Documents

• Apr 18, 2022
• 4 minutes to read

PDF Graphics allows you to create and remove link annotations (hypertext links to a URI or document page).

Create a Link

Use the PdfGraphics.AddLinkToUri or PdfGraphics.AddLinkToPage method to create a link to a URI or document page, respectively. These methods use the world coordinate system. Pass a RectangleF object to these methods to specify where a link should appear on the page. Define the page area in points (1/72 of an inch).

Note

You need a reference to the DevExpress.Pdf.Drawing assembly to access the PdfGraphics class.

After you create a link at the specified page area, call one of the following methods to draw graphics content on a page:

PdfGraphics.AddToPageForeground, PdfGraphics.AddToPageBackground

These methods allow you to draw content on an existing page.

PdfDocumentProcessor.RenderNewPage

Draws content on a new page.

Create a Link to a URI

The code sample below demonstrates how to use the PdfGraphics.AddLinkToUri method to create a link to a URI.

View Example

Program.cs

using DevExpress.Pdf;
using System;
using System.Drawing;

namespace AddLinkToUri
{
    class Program
    {
        static void Main(string[] args)
        {

            using (PdfDocumentProcessor processor = new PdfDocumentProcessor())
            {
                // Create an empty document.
                processor.CreateEmptyDocument("..\\..\\Result.pdf");

                // Create and draw graphics.
                using (PdfGraphics graphics = processor.CreateGraphics())
                {
                    using (Font font = new Font("Arial", 34))
                    {
                        SolidBrush blue = (SolidBrush)Brushes.Blue;

                        // Calculate the link size
                        SizeF stringSize = graphics.MeasureString("https://www.devexpress.com", font);
                        RectangleF stringRect = new RectangleF(100, 150, stringSize.Width, stringSize.Height);

                        // Draw a link text. 
                        graphics.DrawString("https://www.devexpress.com", font, blue, stringRect);

                        // Create a link to a URI at the specified page area.
                        graphics.AddLinkToUri(stringRect, new Uri("https://www.devexpress.com"));
                    }

                    // Render a page with graphics.
                    processor.RenderNewPage(PdfPaperSize.Letter, graphics);
                }
            }

        }
    }
}

Program.vb

Imports DevExpress.Pdf
Imports System
Imports System.Drawing

Namespace AddLinkToUri

    Friend Class Program

        Shared Sub Main(ByVal args As String())
            Using processor As PdfDocumentProcessor = New PdfDocumentProcessor()
                ' Create an empty document.
                processor.CreateEmptyDocument("..\..\Result.pdf")
                ' Create and draw graphics.
                Using graphics As PdfGraphics = processor.CreateGraphics()
                    Using font As Font = New Font("Arial", 34)
                        Dim blue As SolidBrush = CType(Brushes.Blue, SolidBrush)
                        ' Calculate the link size
                        Dim stringSize As SizeF = graphics.MeasureString("https://www.devexpress.com", font)
                        Dim stringRect As RectangleF = New RectangleF(100, 150, stringSize.Width, stringSize.Height)
                        ' Draw a link text. 
                        graphics.DrawString("https://www.devexpress.com", font, blue, stringRect)
                        ' Create a link to a URI at the specified page area.
                        graphics.AddLinkToUri(stringRect, New Uri("https://www.devexpress.com"))
                    End Using

                    ' Render a page with graphics.
                    processor.RenderNewPage(PdfPaperSize.Letter, graphics)
                End Using
            End Using
        End Sub
    End Class
End Namespace

Create a Link to a Page

The code sample below demonstrates how to use the PdfGraphics.AddLinkToPage method to create a link to a page.

View Example

Program.cs

using DevExpress.Pdf;
using System.Drawing;


namespace AddLinkToPage
{
    class Program
    {
        static void Main(string[] args)
        {            

            using (PdfDocumentProcessor processor = new PdfDocumentProcessor())
            {
                // Create an empty document.
                processor.CreateEmptyDocument("..\\..\\Result.pdf");

                // Create a PdfGraphics class instance.
                using (PdfGraphics graphics = processor.CreateGraphics())
                {
                    // Draw link text.
                    SolidBrush black = (SolidBrush)Brushes.Black;
                    using (Font font = new Font("Times New Roman", 32, FontStyle.Bold))
                    {
                        graphics.DrawString("PDF Document API", font, black, 180, 150);
                    }

                    // Create a link to the second document page.
                    // Specify the page destination to which the link should refer.
                    graphics.AddLinkToPage(new RectangleF(180, 160, 480, 30), 2, 168, 230);

                    // Render a page with graphics.
                    processor.RenderNewPage(PdfPaperSize.Letter, graphics);

                    // Create the second document page to which the link navigates.
                    processor.AddNewPage(PdfPaperSize.A4);
                }
            }
        }
    }
}

Program.vb

Imports DevExpress.Pdf
Imports System.Drawing

Namespace AddLinkToPage

    Friend Class Program

        Shared Sub Main(ByVal args As String())
            Using processor As PdfDocumentProcessor = New PdfDocumentProcessor()
                ' Create an empty document.
                processor.CreateEmptyDocument("..\..\Result.pdf")
                ' Create and draw graphics.
                Using graphics As PdfGraphics = processor.CreateGraphics()
                    DrawGraphics(graphics)
                    ' Create a link to a page specifying link area, the page number and X, Y destinations.
                    graphics.AddLinkToPage(New RectangleF(180, 160, 480, 30), 1, 168, 230)
                    ' Render a page with graphics.
                    processor.RenderNewPage(PdfPaperSize.Letter, graphics)
                End Using
            End Using
        End Sub

        Private Shared Sub DrawGraphics(ByVal graphics As PdfGraphics)
            ' Draw a text line on the page. 
            Dim black As SolidBrush = CType(Brushes.Black, SolidBrush)
            Using font As Font = New Font("Times New Roman", 32, FontStyle.Bold)
                graphics.DrawString("PDF Document Processor", font, black, 180, 150)
            End Using
        End Sub
    End Class
End Namespace